Barrett, from Millis, Massachusetts, was running third in the late stages of the hotly-contested race when he drove through and by Bonsignore and Santos - who had been the dominant cars of the night - on Lap 139. The 19-year-old held on to the lead in his No. 22 Canto Paving/Ferguson Waterworks Chevrolet through one final restart on Lap 146 for the milestone first victory.

It was just his 10th career start, and first time competing in the sixth annual combination race between the Whelen Modified and Whelen Southern Modified Tours.

Santos held on for a runner-up finish and Ron Silk joined him on the podium in third. Whelen Modified points leader Doug Coby crossed the line fourth and NASCAR Sprint Cup Series veteran Ryan Newman was fifth.

Bonsignore, the event's Coors Light Pole Award winner, slipped to sixth in the final running order followed by Eric Goodale, Patrick Emerling, Timmy Solomito and Jimmy Zacharias.

JR Bertuccio ended up as the highest-finishing Whelen Southern Modified Tour driver in the event, 13th overall, and was credited with a victory for that tour. Southern tour points leader Andy Seuss was scored 27th in the final rundown.

With Barrett's win Wednesday, his Our Racing team has won at Bristol two years in a row. Mike Stefanik drove the No. 22 to Victory Lane in 2013.

The Bush's Beans 150 will air on Fox Sports 1 on Aug. 31 at 12 p.m. EDT.

With four events remaining on the Whelen Modified Tour schedule, Coby leads Bonsignore 407-403 in the championship standings with Ted Christopher in third at 374. The Whelen Southern Modified Tour has seven events remaining and Seuss now leads George Brunnhoelzl III 301-286 with Bertuccio ranked third at 274.

The NASCAR Whelen Southern Modified Tour will return to action with the Bayport Credit Union 150 on Aug. 30 at Langley Speedway in Hampton, Virginia, while the NASCAR Whelen Modified Tour will be idle until the Riverhead 200 on Sept. 13 at Riverhead Raceway on New York's Long Island.